Duplicate Phase 1 Packet detected. ASA 5520 Client Access

We have a user that is getting a Duplicate Phase 1 Packet detected. Retransmitting last Packet. He is using Cisco VPN Client Software 5.0.01.0600. He is using Windows XP and going through a Dlink DIR 625. We are seeing him connect to the ASA5520 running Version 7.2(2) getting the above error. There is no previous version of Cisco client software on the PC and the firewall is off.